Been lurking for a little while, but finally signed up. I'm 51 with a 49 yo wife, and 2 kids - 17 and 14. Had a buddy just retire at 57, and it got me to thinking. We've paid off the house and cars - no debt. We've saved $4.6MM total, with about $900K in 401Ks and the balance in after-tax savings. On top of that, we have $150K set aside for the kid's college. Our expenses are ~100K each year. I have run this through a lot of calculators, and they all say we are good. But it still makes me a little nervous. Am I just being overly conservative?